Harley Davidson Primary Drive Locking Tool for Motor Sprocket and Clutch Hub Nut Must have tool for any Harley Davidson owner! Use this universal cam lock tool to lock the primary drive when installing and removing primary drive components (such as motor sprocket and clutch hub nut). CNC machined from high quality non-marring Delrin plastic which means it will not scratch or harm your vehicle and is built to last. Works on both the clutch and transmission side! This universal tool is used to wedge into the primary drive sprocket and lock it in place while removing and installing components.